Organic Letters,
Год журнала:
2019,
Номер
21(20), С. 8454 - 8458
Опубликована: Окт. 10, 2019
A
first
example
of
radical
hydroboration
and
hydrosilylation
gem-difluoroalkenes
using
ABIN
as
the
initiator
is
described.
This
protocol
features
good
functional
group
tolerance,
operational
simplicity,
high
atom
economy,
easy
scale-up,
enabling
efficient
assembly
a
wide
range
α-difluorinated
alkylborons
alkylsilanes
in
moderate
to
excellent
yields.
The
synthetic
utility
these
products
demonstrated
by
further
transformation
C–B
bond
C–Si
into
valuable
CF2-containing
molecules.
Chemical Reviews,
Год журнала:
2021,
Номер
121(7), С. 3561 - 3597
Опубликована: Фев. 17, 2021
Organoboron
compounds
have
important
synthetic
value
and
can
be
applied
in
numerous
transformations.
The
development
of
practical
convenient
ways
to
synthesize
boronate
esters
has
thus
attracted
significant
interest.
Photoinduced
borylations
originated
from
stoichiometric
reactions
alkanes
arenes
with
well-defined
metal–boryl
complexes.
Now,
photoredox-initiated
borylations,
catalyzed
by
either
transition
metal
or
organic
photocatalysts,
photochemical
high
efficiency
become
a
burgeoning
area
research.
In
this
Focus
Review,
we
summarize
research
on
photoinduced
especially
emphasizing
recent
developments
trends.
This
includes
the
borylation
arenes,
alkanes,
aryl/alkyl
halides,
activated
carboxylic
acids,
amines,
alcohols,
so
based
catalysis,
metal-free
organocatalysis,
direct
activation.
We
focus
reaction
mechanisms
involving
single-electron
transfer,
triplet-energy
other
radical
processes.
Chemical Reviews,
Год журнала:
2021,
Номер
121(21), С. 13238 - 13341
Опубликована: Окт. 7, 2021
Organoboron
reagents
represent
a
unique
class
of
compounds
because
their
utility
in
modern
synthetic
organic
chemistry,
often
affording
unprecedented
reactivity.
The
transformation
the
carbon–boron
bond
into
carbon–X
(X
=
C,
N,
and
O)
stereocontrolled
fashion
has
become
invaluable
medicinal
agrochemistry,
natural
products
chemistry
as
well
materials
science.
Over
past
decade,
first-row
d-block
transition
metals
have
increasingly
widely
used
catalysts
for
formation
bond,
traditionally
catalyzed
by
expensive
precious
metals.
This
recent
focus
on
alternative
enabled
growth
fundamental
methods
organoboron
chemistry.
review
surveys
current
state-of-the-art
use
element-based
bonds.
Science,
Год журнала:
2021,
Номер
371(6535), С. 1232 - 1240
Опубликована: Март 5, 2021
Defluorinative
functionalization
of
readily
accessible
trifluoromethyl
groups
constitutes
an
economical
route
to
partially
fluorinated
molecules.
However,
the
controllable
replacement
one
or
two
fluorine
atoms
while
maintaining
high
chemoselectivity
remains
a
formidable
challenge.
Here
we
describe
general
strategy
for
sequential
carbon-fluorine
(C-F)
bond
functionalizations
trifluoroacetamides
and
trifluoroacetates.
The
reaction
begins
with
activation
carbonyl
oxygen
atom
by
4-dimethylaminopyridine-boryl
radical,
followed
spin-center
shift
trigger
C-F
scission.
A
chemoselectivity-controllable
two-stage
process
enables
generation
difluoro-
monofluoroalkyl
radicals,
which
are
selectively
functionalized
different
radical
traps
afford
diverse
products.
mechanism
origin
were
established
experimental
computational
approaches.
Angewandte Chemie International Edition,
Год журнала:
2020,
Номер
59(31), С. 12876 - 12884
Опубликована: Март 31, 2020
Radical
borylation
using
N-heterocyclic
carbene
(NHC)-BH3
complexes
as
boryl
radical
precursors
has
emerged
an
important
synthetic
tool
for
organoboron
assembly.
However,
the
majority
of
reported
methods
are
limited
to
reaction
modes
involving
carbo-
and/or
hydroboration
specific
alkenes
and
alkynes.
Moreover,
generation
NHC-boryl
radicals
relies
principally
on
hydrogen
atom
abstraction
with
aid
initiators.
A
distinct
method
is
reported,
well
pathways
enabled
by
photoredox
catalysis.
generated
via
a
single-electron
oxidation
subsequently
undergo
cross-coupling
in-situ-generated
anions
yield
gem-difluoroallylboronates.
photoredox-catalyzed
arylboration
was
achieved
cyanoarenes
arylating
components
from
which
elaborated
organoborons
were
accessed.
Mechanistic
studies
verified
oxidative
formation
through
single-electron-transfer
pathway.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(29), С. 11251 - 11261
Опубликована: Июль 16, 2021
Radical
hydroalkylation
of
olefins
enabled
by
hydrogen
atom
transfer
(HAT)
catalysis
represents
a
straightforward
means
to
access
C(sp3)-rich
molecules
from
abundant
feedstock
chemicals
without
the
need
for
prefunctionalization.
While
Giese-type
activated
initiated
HAT
hydridic
carbon-hydrogen
bonds
is
well-precedented,
unactivated
in
similar
fashion
remains
elusive,
primarily
owing
lack
general
methods
overcome
inherent
polarity-mismatch
this
scenario.
Here,
we
report
use
visible-light-driven
dual
achieve
goal,
where
catalytic
amounts
an
amine-borane
and
situ
generated
thiol
were
utilized
as
abstractor
donor,
respectively.
The
reaction
completely
atom-economical
exhibits
broad
scope.
Experimental
computational
studies
support
proposed
mechanism
suggest
that
hydrogen-bonding
between
substrates
beneficial
improving
efficiency.
Journal of the American Chemical Society,
Год журнала:
2022,
Номер
144(19), С. 8551 - 8559
Опубликована: Апрель 4, 2022
A
new
strategy
for
the
direct
cleavage
of
C(sp3)-OH
bond
has
been
developed
via
activation
free
alcohols
with
neutral
diphenyl
boryl
radical
generated
from
sodium
tetraphenylborate
under
mild
visible
light
photoredox
conditions.
This
verified
by
cross-electrophile
coupling
and
carbon
dioxide
synthesis
carboxylic
acids.
Direct
transformation
a
range
primary,
secondary,
tertiary
benzyl
to
acids
achieved.
Control
experiments
computational
studies
indicate
that
undergoes
homolysis
bond,
generating
alkyl
radicals.
After
reducing
into
anion
conditions,
following
carboxylation
CO2
affords
product.
